Irradiated peripheral blood mononuclear cells for assessing individual radiosensitivity in laryngeal cancer radiotherapy

In laryngeal cancer radiotherapy (LCRT), dermatitis, dysphagia, and odynophagia are common acute side effects, varying in intensity depending mainly on the patient's radiosensitivity. This study investigated the survival rate of in vitro irradiated peripheral blood mononuclear cells (PBMC) as a pre-therapeutic test to assess individual radiosensitivity and predict the degree of these acute side effects in LCRT. 16 patients diagnosed with early-stage laryngeal cancer undergoing radiotherapy without adjuvant chemotherapy participated as volunteers in this study. Before the beginning of treatment, a sample of PBMC was collected and irradiated with 2.5 Gy using a 6 MV linear accelerator. After 72-h cell incubation, the trypan blue exclusion test was performed to score viable cells through optical microscopy. The percentages of cell viability were compared to the intensity of acute side effects experienced by LCRT patients. Even though no correlation was found regarding the observed degrees of radiation dermatitis, our results indicate that patients with survival rates of in vitro irradiated PBMC higher than 70% are more likely to experience moderate to severe acute odynophagia and dysphagia after LCRT. The proposed and discussed methodology points to a practical and affordable pre-therapeutic test to evaluate individual radiosensitivity in order to prevent or reduce acute side effects in laryngeal cancer radiotherapy.